JPH11310099A - Driver's seat air bag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driver's seat air bag device whose flat switch for a horn is turned on by slightly pushing a module cover and dispensing with the need to raise inflation capacity. SOLUTION: The crew facing surface of a module cover 18 is divided into flaps 40, 42 by tear lines 32, 34. A flat switch 50 is arranged so that it may face only to the flap 40 and is backed up by a back up plate 60. A body 62 of the back up plate 60 faces only to the flap 40. A fitting piece 64 extending from the body 62 is connected to a retainer and an extension piece 66 protruding to the right and left is locked to an opening 80 of the module cover leg.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device for a driver's seat installed on a steering wheel of an automobile, and more particularly to an airbag device for a driver's seat provided with a horn switch behind an occupant-facing surface of a module cover.

[0002]

2. Description of the Related Art In a driver's seat airbag device, an inflator and an airbag are attached to a retainer as is well known, and a module cover covers the airbag.
The module cover is provided with a tear line, and when the inflator is activated and the airbag is inflated, the module cover is torn along the tear line and the airbag spreads in the vehicle interior. When the module cover is torn along the tear line, a tongue-shaped flap is formed on the module cover, and the flap opens to the vehicle interior.

[0003] In such an airbag device for a driver's seat, there is a device in which a horn switch is disposed behind an occupant-facing surface of a module cover. In this case, the horn of the automobile sounds by pressing the occupant facing surface of the module cover.
2. Description of the Related Art An airbag device for a driver's seat in which a planar horn switch (hereinafter, referred to as a planar switch) is supported by a backup plate so that a horn switch can be turned on simply by lightly pressing a module cover is known. (For example, JP-A-8-188109, JP-A-9-66793
issue).

[0004]

In the above-described known airbag device for a driver's seat, a backup plate is provided over substantially the entire occupant-facing surface of the module cover, and both ends of the backup plate are supported by a retainer. Switch can be firmly backed up. In this case, since the backup plate is disposed across the tear line of the module cover, the backup plate is also provided with a tear line along the tear line on the occupant-facing surface of the module cover. When the airbag is inflated by the gas released from the inflator, it is necessary to tear not only the module cover but also this backup plate along the tear line, so it is necessary to use an inflator with a higher gas generation pressure. There is.

If the backup plate is arranged only within the area of one tongue surrounded by the tear line on the occupant-facing surface of the module cover, it is not necessary to provide the backup plate with a tear line. Is cantilevered with only one end supported by the retainer, so if the planar switch is pressed,
The backup plate easily retreats together with the planar switch, and the planar switch (horn switch) does not turn on unless the occupant-facing surface of the module cover is pressed so strongly.

According to the present invention, there is no tear line in the backup plate, the airbag can be inflated sufficiently quickly even with a small-output inflator, and the planar switch can be turned on by lightly pressing the occupant-facing surface of the module cover. It is an object to provide an airbag device for a driver's seat.

[0007]

SUMMARY OF THE INVENTION An airbag device for a driver's seat according to the present invention includes a retainer to which an airbag and an inflator are attached, a module cover for covering the airbag, and a rear face of an occupant-facing surface of the module cover. The module cover includes a backup plate disposed, and a planar switch disposed between the occupant-facing surface of the module cover and the backup plate, and the module cover is erected from the occupant-facing surface and attached to the retainer. A main body facing the occupant-facing surface, and a mounting piece extending from the main body along the leg and attached to the retainer. The module cover having at least one tongue demarcated by a tear line. In the above, the main body of the backup plate faces only one tongue piece, and the backup plate includes an extension piece extending from the main body, and the extension piece is attached to the module. The main body is locked to an opening or a recess provided in the leg of the cover so as to prevent the body from retreating toward the retainer.

In such a driver's seat airbag device, the backup plate is disposed only within a range of one tongue portion surrounded by the tear line of the module cover, and the backup plate has no tear line. When the airbag is inflated, the backup plate is pushed by the airbag without being torn and is quickly deformed.

Further, the backup plate has an extending piece, which is locked to the leg of the module cover and is prevented from retreating to the retainer side. The surface switch is turned ON simply by pressing lightly.

It is preferable that the extending pieces are provided so as to extend in opposite directions with respect to the main body.
Further, it is preferable that the opening or the concave portion is provided in a portion near the occupant facing surface of the leg portion.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1 (a) is a plan view of an airbag device for a driver's seat according to an embodiment, FIG. 1 (b) is a cross-sectional view taken along the line BB of FIG. 1 (a), and FIG. It is a perspective view which shows the engagement relationship of a switch and a backup plate.

The retainer 10 has a flat plate portion 14 to which the airbag 12 is mounted, and a module cover mounting portion consisting of an upright piece 16 standing upright from the edge of the flat plate portion 14 in the direction opposite to the occupant. The airbag 12 is covered with a module cover 18 in a folded state. The module cover 18 includes a main plate surface 18A facing the occupant, and a standing piece 18B erected from a side of the main plate surface in a direction opposite to the occupant.
And The standing piece 18B is connected to the retainer 1
0 is fixed to the upright piece 16 by a rivet 20. Reference numeral 22 denotes a deposit.

The inflator 24 is fixed to the retainer 10 such that the upper end of the inflator 24 enters the airbag 12 through an opening 26 formed in the flat plate portion 14. Reference numeral 28 denotes an airbag attachment member called a ring, which sandwiches the opening edge of the airbag 12 between the ring 28 and the edge of the opening 24 of the flat plate portion 14, whereby the airbag 12
Are fixed to the retainer 10. Although not shown, bolts are fixed to the ring 28, and the bolts are inserted into bolt insertion holes provided in the opening edge of the airbag 12, the retainer flat plate portion 14 and the flange 24 a of the inflator 24, A nut is fastened to the bolt.

The main plate surface 18A of the module cover 18
Are provided with tear lines 30, 32, and 34 for cleaving the main plate surface 18A. The tear lines 30, 32 extend in the vertical direction in FIG. 1A along the leg pieces 18B on the left side and the right side in FIG. 1A. The tear line 34 extends substantially in the center of the main plate surface 18A in the left-right direction of FIG. 1A so as to connect the tear lines 30 and 32 to each other.

By being surrounded by the tear lines 30, 32, and 34, the module cover main plate surface 18A is partitioned into two regions (flaps 40 and 42). When the inflator 22 inflates the airbag 12 by injecting gas, the module cover 18 is connected to the tear lines 30 and 3.
The portions 2 and 34 are torn, and the flaps 40 and 42 can be opened outwardly in a tongue shape.

A horn planar switch 50 is arranged so as to face only the upper flap 40 in FIG. 1 (a). Reference numeral 52 denotes a lead wire of the planar switch 50. A backup plate 60 is provided to back up the planar switch 50.
Is interposed between the backup plate 60 and the module cover main plate surface 18A (flap 40).

The planar switch 50 is fixed to the backup plate 60 by inserting a boss 61 projecting from the backup plate 60 into the hole 55 of the planar switch 50 and heat caulking. The fixing method of both may be other than this.

The backup plate 60 has a main body 62 facing the planar switch 50 and a mounting piece 64 extending from the main body 62. This mounting piece 6
Reference numeral 4 extends along the leg piece 18B of the module cover 18 and is sandwiched between the leg piece 18B and the retainer standing piece 16. Then, rivets are set through rivet holes 70 and 72 (FIG. 2) provided in the leg piece portion 18B and the mounting piece portion 64 (FIG. 2) and a rivet hole (not shown) of the upstanding piece 16 so that the mounting piece portion 64 is formed. Is connected to the retainer 10.

The main body 62 of the backup plate 60 is provided with a protruding piece 66 extending in the left-right direction in FIG. The extending piece 66 crosses the tear lines 30 and 32 and is engaged with the opening 80 of the leg portion 18B. As shown in FIG. 1B, since the extension piece 66 is in contact with the lower edge of the opening 80, the planar switch 50 and the backup plate 6 are pressed when the module cover main plate surface 18A is pressed.
0 does not retreat, and the planar switch 50 is turned ON.

As shown, the opening 80 is provided in the leg piece 80 near the main plate surface 18A. For this reason, the extension piece 66 is protruded substantially sideways from the main body 62. Since the extension piece is bent in a crank shape as shown in FIG. 1B, the bent portion of the extension piece is easily deformed when the airbag is inflated.

In the event of a vehicle collision, the inflator 24
When the inflator 24 operates, a large amount of gas is rapidly discharged from the inflator 24.
And the airbag 12 starts to deploy. Then, with the deployment of the airbag 12, the module cover 18 is torn along the tear lines 30, 32, 34, and the flaps 40, 42 are opened in a tongue-like manner.
Deploys rapidly into the cabin to protect occupants.

When the airbag 12 is inflated, the backup plate 60 is attached to the mounting piece 64 near the main body 62.
Is deformed, and the main body 62 opens together with the flap 40 toward the vehicle interior. At this time, the extension piece 66 is also deformed,
It comes off the opening 80.

The main body 6 of the backup plate 60
2 faces the flap 40 only, the tear line 3
Because it does not straddle 0, 32, 34, tear line 3
There is no hindrance to the initiation of cleavage at 0, 32, 34. In addition, when the airbag 12 is deployed, the backup plate 60 simply deforms the attachment piece 64 and the extension piece 66,
There is no obstacle to the deployment of the airbag 12. Therefore, the inflator 24 does not need to have a high gas generation pressure.

In the above embodiment, the extension piece 66 is engaged with the opening 80 of the leg portion 18B, but a concave portion may be provided on the inner surface of the leg portion 18B instead of the opening 80. .

[0025]

As described in detail above, according to the airbag device for the driver's seat of the present invention, the horn planar switch is turned on by lightly pressing the module cover. Further, in the present invention, the airbag can be deployed at a predetermined speed without increasing the gas generation pressure of the inflator.

[Brief description of the drawings]

FIG. 1A is a plan view of an airbag device for a driver's seat according to an embodiment of the present invention, and FIG. 1B is a BB view of FIG.
It is sectional drawing which follows a line.

FIG. 2 is a perspective view showing a module cover, a planar switch and a backup plate of the airbag device for a driver's seat shown in FIG. 1;

[Explanation of symbols]

 Reference Signs List 10 retainer 12 air bag 18 module cover 18A main plate surface 18B leg piece 24 inflator 30, 32, 34 tear line 40, 42 flap 50 planar switch 60 backup plate 62 main body 64 mounting piece 66 extension piece 70, 72 rivet hole 80 Opening

Claims (3)

[Claims] 1. A retainer to which an airbag and an inflator are attached, a module cover for covering the airbag, a backup plate disposed on a rear side of an occupant-facing surface of the module cover, and an occupant-facing surface of the module cover. A planar switch disposed between the backup plate and the backup plate, wherein the module cover has a leg portion erected from the occupant-facing surface and attached to the retainer; A main body facing the occupant-facing surface; and a mounting piece extending from the main body along the leg piece and attached to the retainer, wherein the module cover is partitioned by a tear line. An airbag device for a driver seat having at least one tongue piece, wherein a main body of the backup plate is provided. The backup plate has only one tongue piece, and the backup plate has an extension piece extending from the main body, and the extension piece is provided on a leg piece of the module cover. An airbag device for a driver's seat, wherein the opening or the recess is locked so as to prevent the main body from retreating to the retainer side. 2. The airbag device for a driver's seat according to claim 1, wherein the extension pieces are provided so as to extend in opposite directions with respect to the main body. 3. The airbag device for a driver's seat according to claim 1, wherein the opening or the concave portion is provided in a portion of the leg portion near an occupant facing surface.